openldap: run under systemd-defined user/group
This improves security, by starting the service as an unprivileged user, rather than starting as root and relying on the service to drop privileges. This requires a significant cleanup of pre-init scripts, to make use of StateDirectory and RuntimeDirectory for permissions.
This commit is contained in:
Kai Wohlfahrt
Jörg Thalheim
parent
38ead944ce
commit
fd7d901133
|
|
@ -10,7 +10,15 @@ let
|
|||
# Can't do types.either with multiple non-overlapping submodules, so define our own
|
||||
singleLdapValueType = lib.mkOptionType rec {
|
||||
name = "LDAP";
|
||||
description = "LDAP value";
|
||||
# TODO: It would be nice to define a { secret = ...; } option, using
|
||||
# systemd's LoadCredentials for secrets. That would remove the last
|
||||
# barrier to using DynamicUser for openldap. This is blocked on
|
||||
# systemd/systemd#19604
|
||||
description = ''
|
||||
LDAP value - either a string, or an attrset containing
|
||||
<literal>path</literal> or <literal>base64</literal> for included
|
||||
values or base-64 encoded values respectively.
|
||||
'';
|
||||
check = x: lib.isString x || (lib.isAttrs x && (x ? path || x ? base64));
|
||||
merge = lib.mergeEqualOption;
|
||||
};
|
||||
|
|
@ -80,9 +88,7 @@ in {
|
|||
enable = mkOption {
|
||||
type = types.bool;
|
||||
default = false;
|
||||
description = "
|
||||
Whether to enable the ldap server.
|
||||
";
|
||||
description = "Whether to enable the ldap server.";
|
||||
};
|
||||
|
||||
package = mkOption {
|
||||
|
|
@ -147,7 +153,7 @@ in {
|
|||
attrs = {
|
||||
objectClass = [ "olcDatabaseConfig" "olcMdbConfig" ];
|
||||
olcDatabase = "{1}mdb";
|
||||
olcDbDirectory = "/var/db/ldap";
|
||||
olcDbDirectory = "/var/lib/openldap/ldap";
|
||||
olcDbIndex = [
|
||||
"objectClass eq"
|
||||
"cn pres,eq"
|
||||
|
|
@ -171,7 +177,18 @@ in {
|
|||
Use this config directory instead of generating one from the
|
||||
<literal>settings</literal> option. Overrides all NixOS settings.
|
||||
'';
|
||||
example = "/var/db/slapd.d";
|
||||
example = "/var/lib/openldap/slapd.d";
|
||||
};
|
||||
|
||||
mutableConfig = mkOption {
|
||||
type = types.bool;
|
||||
default = false;
|
||||
description = ''
|
||||
Whether to allow writable on-line configuration. If
|
||||
<literal>true</literal>, the NixOS settings will only be used to
|
||||
initialize the OpenLDAP configuration if it does not exist, and are
|
||||
subsequently ignored.
|
||||
'';
|
||||
};
|
||||
|
||||
declarativeContents = mkOption {
|
||||
|
|
@ -185,6 +202,11 @@ in {
|
|||
reboot of the server. Performance-wise the database and indexes are
|
||||
rebuilt on each server startup, so this will slow down server startup,
|
||||
especially with large databases.
|
||||
|
||||
Note that the root of the DB must be defined in
|
||||
<code>services.openldap.settings</code> and the
|
||||
<code>olcDbDirectory</code> must begin with
|
||||
<literal>"/var/lib/openldap"</literal>.
|
||||
'';
|
||||
example = lib.literalExpression ''
|
||||
{
|
||||
|
|
@ -207,7 +229,49 @@ in {
|
|||
|
||||
meta.maintainers = with lib.maintainers; [ mic92 kwohlfahrt ];
|
||||
|
||||
config = mkIf cfg.enable {
|
||||
config = let
|
||||
dbSettings = mapAttrs' (name: { attrs, ... }: nameValuePair attrs.olcSuffix attrs)
|
||||
(filterAttrs (name: value: hasPrefix "olcDatabase=" name) cfg.settings.children);
|
||||
settingsFile = pkgs.writeText "config.ldif" (lib.concatStringsSep "\n" (attrsToLdif "cn=config" cfg.settings));
|
||||
writeConfig = pkgs.writeShellScript "openldap-config" ''
|
||||
set -euo pipefail
|
||||
|
||||
${lib.optionalString (!cfg.mutableConfig) "rm -rf ${configDir}/*"}
|
||||
if [ ! -e "${configDir}/cn=config.ldif" ]; then
|
||||
${openldap}/bin/slapadd -F ${configDir} -bcn=config -l ${settingsFile}
|
||||
fi
|
||||
chmod -R ${if cfg.mutableConfig then "u+rw" else "u+r-w"} ${configDir}
|
||||
'';
|
||||
|
||||
contentsFiles = mapAttrs (dn: ldif: pkgs.writeText "${dn}.ldif" ldif) cfg.declarativeContents;
|
||||
writeContents = pkgs.writeShellScript "openldap-load" ''
|
||||
rm -rf /var/lib/openldap/$2/*
|
||||
${openldap}/bin/slapadd -F ${configDir} -b $1 -l $3
|
||||
'';
|
||||
in mkIf cfg.enable {
|
||||
assertions = [{
|
||||
assertion = (cfg.declarativeContents != {}) -> cfg.configDir == null;
|
||||
message = ''
|
||||
Declarative DB contents (${attrNames cfg.declarativeContents}) are not
|
||||
supported with user-managed configuration.
|
||||
'';
|
||||
}] ++ (map (dn: {
|
||||
assertion = (getAttr dn dbSettings) ? "olcDbDirectory";
|
||||
# olcDbDirectory is necessary to prepopulate database using `slapadd`.
|
||||
message = ''
|
||||
Declarative DB ${dn} does not exist in `services.openldap.settings`, or does not have
|
||||
`olcDbDirectory` configured.
|
||||
'';
|
||||
}) (attrNames cfg.declarativeContents)) ++ (mapAttrsToList (dn: { olcDbDirectory ? null, ... }: {
|
||||
# For forward compatibility with `DynamicUser`, and to avoid accidentally clobbering
|
||||
# directories with `declarativeContents`.
|
||||
assertion = (olcDbDirectory != null) ->
|
||||
((hasPrefix "/var/lib/openldap/" olcDbDirectory) && (olcDbDirectory != "/var/lib/openldap/"));
|
||||
message = ''
|
||||
Database ${dn} has `olcDbDirectory` (${olcDbDirectory}) that is not a subdirectory of
|
||||
`/var/lib/openldap/`.
|
||||
'';
|
||||
}) dbSettings);
|
||||
environment.systemPackages = [ openldap ];
|
||||
|
||||
# Literal attributes must always be set
|
||||
|
|
@ -231,46 +295,31 @@ in {
|
|||
];
|
||||
wantedBy = [ "multi-user.target" ];
|
||||
after = [ "network-online.target" ];
|
||||
preStart = let
|
||||
settingsFile = pkgs.writeText "config.ldif" (lib.concatStringsSep "\n" (attrsToLdif "cn=config" cfg.settings));
|
||||
|
||||
dbSettings = lib.filterAttrs (name: value: lib.hasPrefix "olcDatabase=" name) cfg.settings.children;
|
||||
dataDirs = lib.mapAttrs' (name: value: lib.nameValuePair value.attrs.olcSuffix value.attrs.olcDbDirectory)
|
||||
(lib.filterAttrs (_: value: value.attrs ? olcDbDirectory) dbSettings);
|
||||
dataFiles = lib.mapAttrs (dn: contents: pkgs.writeText "${dn}.ldif" contents) cfg.declarativeContents;
|
||||
mkLoadScript = dn: let
|
||||
dataDir = lib.escapeShellArg (getAttr dn dataDirs);
|
||||
in ''
|
||||
rm -rf ${dataDir}/*
|
||||
${openldap}/bin/slapadd -F ${lib.escapeShellArg configDir} -b ${dn} -l ${getAttr dn dataFiles}
|
||||
chown -R "${cfg.user}:${cfg.group}" ${dataDir}
|
||||
'';
|
||||
in ''
|
||||
mkdir -p /run/slapd
|
||||
chown -R "${cfg.user}:${cfg.group}" /run/slapd
|
||||
|
||||
mkdir -p ${lib.escapeShellArg configDir} ${lib.escapeShellArgs (lib.attrValues dataDirs)}
|
||||
chown "${cfg.user}:${cfg.group}" ${lib.escapeShellArg configDir} ${lib.escapeShellArgs (lib.attrValues dataDirs)}
|
||||
|
||||
${lib.optionalString (cfg.configDir == null) (''
|
||||
rm -Rf ${configDir}/*
|
||||
${openldap}/bin/slapadd -F ${configDir} -bcn=config -l ${settingsFile}
|
||||
'')}
|
||||
chown -R "${cfg.user}:${cfg.group}" ${lib.escapeShellArg configDir}
|
||||
|
||||
${lib.concatStrings (map mkLoadScript (lib.attrNames cfg.declarativeContents))}
|
||||
${openldap}/bin/slaptest -u -F ${lib.escapeShellArg configDir}
|
||||
'';
|
||||
serviceConfig = {
|
||||
User = cfg.user;
|
||||
Group = cfg.group;
|
||||
ExecStartPre = [
|
||||
"!${pkgs.coreutils}/bin/mkdir -p ${configDir}"
|
||||
"+${pkgs.coreutils}/bin/chown $USER ${configDir}"
|
||||
] ++ (lib.optional (cfg.configDir == null) writeConfig)
|
||||
++ (mapAttrsToList (dn: content: lib.escapeShellArgs [
|
||||
writeContents dn (getAttr dn dbSettings).olcDbDirectory content
|
||||
]) contentsFiles)
|
||||
++ [ "${openldap}/bin/slaptest -u -F ${configDir}" ];
|
||||
ExecStart = lib.escapeShellArgs ([
|
||||
"${openldap}/libexec/slapd" "-d" "0" "-u" cfg.user "-g" cfg.group "-F" configDir
|
||||
"-h" (lib.concatStringsSep " " cfg.urlList)
|
||||
"${openldap}/libexec/slapd" "-d" "0" "-F" configDir "-h" (lib.concatStringsSep " " cfg.urlList)
|
||||
]);
|
||||
Type = "notify";
|
||||
# Fixes an error where openldap attempts to notify from a thread
|
||||
# outside the main process:
|
||||
# Got notification message from PID 6378, but reception only permitted for main PID 6377
|
||||
NotifyAccess = "all";
|
||||
RuntimeDirectory = "slapd"; # TODO: openldap, for consistency
|
||||
StateDirectory = ["openldap"]
|
||||
++ (map ({olcDbDirectory, ... }: removePrefix "/var/lib/" olcDbDirectory) (attrValues dbSettings));
|
||||
StateDirectoryMode = "700";
|
||||
AmbientCapabilities = [ "CAP_NET_BIND_SERVICE" ];
|
||||
CapabilityBoundingSet = [ "CAP_NET_BIND_SERVICE" ];
|
||||
};
|
||||
};
|
||||
|
||||
|
|
|
|||
|
|
@ -43,7 +43,7 @@ in {
|
|||
attrs = {
|
||||
objectClass = [ "olcDatabaseConfig" "olcMdbConfig" ];
|
||||
olcDatabase = "{1}mdb";
|
||||
olcDbDirectory = "/var/db/openldap";
|
||||
olcDbDirectory = "/var/lib/openldap/db";
|
||||
olcSuffix = "dc=example";
|
||||
olcRootDN = {
|
||||
# cn=root,dc=example
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user